Maximum and minimum recording electric meter.



No. 702,849. Patented lune I7, I902.

- A. WRIGHT.

MAXIMUM AND MINIMUM RECORDING ELEBTRIC'METEB.

(Application filed July 1, 1901.)

3 Sheets-Sheet I.

(No Model.)

Irzuervzf raar 179177: a M

me warm: min: 00.. mm-umo. wuumcmu. a, c.

No. 702,849. Patented lune I7, I902.

A. WRIGHT. MAXIMUM AND MINIMUM RECORDING ELECTRIC METER.

(Application filed July 1, 1901.)

3 Shaets$heat 2.

(No Model) fii ssu:

6 6 wzial No. 702,349. Patented lune l7, I902.

, A. WRIGHT. MAXIMUM AND MINIMUM RECORDING ELECTRIC METER.

(Application filed July 1, 1901, (No Model.) 3 Sheets-Sheet 3,

Wifnesses: I a Z 7 9. 3 g 7 625 we ucnms vzrzns ca,FHOYO-LITHO.,WASH1NGTON, c.

IINTTEE STATES PATENT OFFICE.

ARTHUR IVRIGHT, OF BRIGHTON, ENGLAND, ASSIGNOR TO THE MUTUAL ELECTRICTRUST, LIMITED, OF BRIGHTON, ENGLAND.

MAXIMUM AND MINIMUM RECORDING ELECTRIC METER.

SPECIFICATIUN forming part Of Lettel'S Patent NO. 702,849, dated June17, 1902.

Application filed July 1, I901 Serial No. 66,739- (No model.)

To aZZ whom it may concern.-

Be it known that I, ARTHUR WRIGHT, a subject of the King of GreatBritain, and a resident of Brighton, in the county of Sussex, England,have invented certain new and useful Improvements in Maximum and MinimumRecording Electric Meters, of which the following is a specification.

This invention relates to improvements in maximum and minimum recordingelectric meters of the type set forth in the United States patentgranted to me on the 25th day of May, 1897, and numbered 583,160. Ishall hereinafter refer to the specification of the said patent as myprior specification.

In the accompanying drawings, Figure I is a form corrresponding withthat shown in Fig. 13 of my said prior specification, but embodyingcertain improvements hereinafter to be described. Fig. II illustrateswhat I term a double expansion-head. Fig. III illustrates what I term atreble expansion-head. Fig. IV is a modified form of trebleexpansionhead. Fig. V illustrates a double receptacle. Fig. VIillustrates a treble receptacle. Fig. VI is an elevation of part of amodified form of instrument. Fig. VIII is a side elevation of thereceptacle thereof. Fig. IX is a crosssection on the line co m of Fig.VIII.

The first of myimprovements consists of a novel form of trap (shown inFigs. I, II, and III) for use below the expansion-bulb. The ordinarycompression-bulb is numbered 5, but the expansion-bulb 1 instead ofbeing continuous with the expansion-limb 2 of the U-tube is drawn out atone part to a nozzle 8, and this nozzle is sealed into a trap-bulb 4:,so as to penetrate for some distance thereinto. This form of trap mayconveniently be employed in addition to the usual bubbletrap employed ininstruments of this type, and its object is not only to prevent or aidin preventing the liquid from entering the expansion-bulb on theinstrument being reset, but also to prevent air passing from thecompression-bulb around to the expansion-bulb should any sudden coolingof the expansionbulb take place during resetting.

A second improvement consists in the employment of two expansion-bulbsconnected in a particular way instead of the single expansion-bulbusually employed. When I employ two expansion-bulbs, as aforesaid,instead of causing them to open directly into the limb of the U-tube Icause them to open into a crutch or cross-tube 6, which crutch orcross-tube itself .opens into the expansionlimb 2 of the U-tube. "Thetwo bulbs constitute a novel and useful form of expansionhead,hereinafter termed a double expansion-head, which is very convenient foruse in connection with three-wire circuits, each of the said bulbs beingembraced by a resistance-wire, each of these resistance-wires beingconnected with one of the outersthat is to say, the resistance-wirearound one of the bulbs is connected with the positive and theresistance-wire around the other is connected with the negative.

I may also employ a treble expansion-head for use in connection withcircuits carrying three-phase currents. The three expansionbulbs 1 l 1of this head instead of each directly opening into the limb of theU-tube are connected therewith in the following manner: Two of the bulbsare connected by a cross-tube or crutch 6 after the manner hereinbeforedescribed with reference to thedonblebulb-headusedforthree-wirecircuits. The said crutch or cross-tubein this case, however, instead of itself opening into the expansion-limbof the U-tube opens into one end of a second crutch or cross-tube 7,either directly or by means of a short tube or neck, whilethe third bulbopens into the other end ofthisthesecondcrutchorcross-tube7. This secondcrutch or cross-tube opens into the expansion-limb 2 of the U-tube.

In a modified form of my treble expansionhead instead of employing twocrutches or cross-tubes, as above described, I employ a single crutch orcross-tube 8, into which the three expansion-bulbs open, two of them atthe ends of the said cross-tube and one at the center or otherintermediate part thereof, as shown in Fig. IV.

In a further improvement I make the receptacle or index-tube 9, (seeFig. 1,) within which the liquid which is spilled over collects, ofconical or substantially conical shape. The said conical receiver isarranged with its apex 9 downward,and it serves two functions.

First, it holds a larger amount of liquid than the existing form ofindex-tube and allows of the instrument having a larger range ofregistrationsay from one-twentieth of its fullload capacity. It alsoallows of a large scalereading being obtained with the smaller currentsand owing to the swelling outtoward the top (base) of the cone enablesthe readings to be crowded together at that point, so as to have alonger range of current-readings than if the divisions were equallyplaced over the scale.

In a modified form of receptacle, hereinafter termed my duplexreceptacle, I make the receptacle as shown in Fig. V. Here it will beseen that my duplex receptacle consists of two receptacles orindex-tubes, one, 9, which is that into which the liquid first flows,being of conical form, similar to that shown in Fig. I. From thisbranchesofla second or cylindrical receptacle 10, which may be ofcylindrical or other desired shape. In practice I prefer to make thesecond receptacle 10 of agage not smaller than that of the conicalreceptacle at its broadest part.

When desired, I may cause athird vessel 11 to branch from the secondvessel of the duplex receptacle, so as to constitute, in fact, a triplexreceptacle, as shown in Fig. VI.

In Fig. VII, I show a part elevation, in Fig. VIII a side elevation ofthe receptacle, and in Fig. IX a section on the line 0350 of Fig. VIIIof a form resembling that shown in Fig. I, but with the difference thatthe receptacle, although still conical in form, is-no longer a cone witha circular cross-section. Instead the cross-section of the cone is afiattened ellipse. This form of receptacle I find very convenient inpractice, and I term it my flat conical form of receptacle.

I may graduate my receptacles in any convenient manner or place a scalebeside them for convenience of reading.

The general operation of my meter is that which has been fully describedin my prior patent, above referred to. The operation of the heatingresistance about the expansionbulb causes the liquid in the meter tospill over into theindex tube or tubes, the amount of the liquid in suchtubes being read ofi on the scale. This scale may be so calibrated beenset.

tilted at such an angle as to cause the liquid in the index-tubes toflow back to the compression-bulb.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. A maximum and minimum electric recording-meter comprising anexpansion-bulb, an expansion-limb and a trap between the two,substantially as described.

2. A maximum and minimum electric recording-m eter comprising anexpansion-bulb, a nozzle connected therewith and a trap-bulb surroundingthe nozzle, substantially as described.

3. A maximum and minimum electric recording-meter comprising a pluralityof expansion-bulbs an expansion-limb and a crutch or cross-tubetherebetween, substantially as described.

4. A maximum and minimum electric recording-meter comprising a pluralityof expansion-bulbs, crutches or cross-tubes connected to theexpansion-bulbs and an expansion-limb connected to the crutches,substantially as described.

5. A maximum and minimum electric recording-meter comprising anindex-tube, in which liquid collects, which is of substantiallyconicalform,substantially as described.

6. A maximum and minimum electric recording-meter comprising anindex-tube, in which liquid collects, which is substantially of a fiatconical form, substantially as described.

7. A maximum and minimum electric re-,

cording-meter comprising a series of indextubes connected with eachother at their upper ends, substantially as described.-

8. A maximum and minimum electric recording-meter comprising a series ofindextubes connected with each other and with the meter at their upperends, substantially as described.

9. A maximum and minimum electric recording-meter comprising a series ofindextubes connected with each other at their upper ends, one of saidtubes being conical, substantially as described.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

ARTHUR \VRIGHT.

IVitnesses:

GEO. J. B. FRANKLIN, T. .T. OSMAN.

